Package org.elasticsearch.search.aggregations.matrix.stats

Class RunningStats

java.lang.Object

org.elasticsearch.search.aggregations.matrix.stats.RunningStats

All Implemented Interfaces:

Cloneable, Writeable

public class RunningStats
extends Object
implements Writeable, Cloneable

Descriptive stats gathered per shard. Coordinating node computes final correlation and covariance stats based on these descriptive stats. This single pass, parallel approach is based on: http://prod.sandia.gov/techlib/access-control.cgi/2008/086212.pdf

Nested Class Summary

Nested classes/interfaces inherited from interface org.elasticsearch.common.io.stream.Writeable

Writeable.Reader<V extends Object>, Writeable.Writer<V extends Object>

Field Summary

Fields

Modifier and Type	Field	Description
protected HashMap<String,Long>	counts	counts
protected HashMap<String,HashMap<String,Double>>	covariances	covariance values
protected long	docCount	count of observations (same number of observations per field)
protected HashMap<String,Double>	fieldSum	per field sum of observations
protected HashMap<String,Double>	kurtosis	kurtosis values (fourth moment)
protected HashMap<String,Double>	means	mean values (first moment)
protected HashMap<String,Double>	skewness	skewness values (third moment)
protected HashMap<String,Double>	variances	variance values (second moment)

Constructor Summary

Constructors

Constructor	Description
RunningStats(StreamInput in)	Ctor to create an instance of running statistics

Method Summary

Modifier and Type	Method	Description
void	add(String[] fieldNames, double[] fieldVals)	updates running statistics with a documents field values
RunningStats	clone()
boolean	equals(Object o)
int	hashCode()
void	merge(RunningStats other)	Merges the descriptive statistics of a second data set (e.g., per shard) running computations taken from: http://prod.sandia.gov/techlib/access-control.cgi/2008/086212.pdf
void	writeTo(StreamOutput out)

Methods inherited from class java.lang.Object

finalize, getClass, notify, notifyAll, toString, wait, wait, wait

Field Details

docCount

protected long docCount

count of observations (same number of observations per field)

fieldSum

protected HashMap<String,Double> fieldSum

per field sum of observations

counts

protected HashMap<String,Long> counts

counts

means

protected HashMap<String,Double> means

mean values (first moment)

variances

protected HashMap<String,Double> variances

variance values (second moment)

skewness

protected HashMap<String,Double> skewness

skewness values (third moment)

kurtosis

protected HashMap<String,Double> kurtosis

kurtosis values (fourth moment)

covariances

protected HashMap<String,HashMap<String,Double>> covariances

covariance values

Constructor Details

RunningStats

public RunningStats(StreamInput in)
             throws IOException

Ctor to create an instance of running statistics

Throws:

IOException

Method Details

writeTo

public void writeTo(StreamOutput out)
             throws IOException

Specified by:

writeTo in interface Writeable

Throws:

IOException

add

public void add(String[] fieldNames,
 double[] fieldVals)

updates running statistics with a documents field values

merge

public void merge(RunningStats other)

Merges the descriptive statistics of a second data set (e.g., per shard) running computations taken from: http://prod.sandia.gov/techlib/access-control.cgi/2008/086212.pdf

clone

public RunningStats clone()

Overrides:

clone in class Object

equals

public boolean equals(Object o)

Overrides:

equals in class Object

hashCode

public int hashCode()

Overrides:

hashCode in class Object